Since the industrial revolution, pollution of subsurface environments by heavy metals has increased substantially from anthropogenic sources such as industrial effluents, military munitions manufacturing, and mining activities. Heavy metals cannot be degraded and therefore accumulate in soils, sediments, and groundwater, posing significant health risks to plants, animals, and humans. Because of the threat to the environment and human health, major efforts are underway to develop remediation strategies to treat heavy metal contaminated soil and groundwater. Bioremediation is rapidly gaining popularity as a less expensive alternative to tradition "pump and treat" methods of remediating heavy metal contaminated soils. Although bioremediation relies the natural interaction of microorganisms with heavy metals, its successful use is highly dependent on the complex interactions between microorganisms, hydrological transport, abiotic chemical species, nutrient availability, etc. This complexity makes it extremely difficult to model, design, or implement effective bioremediation strategies. Bioremediation is further complicated by biogeochemical heterogeneity both site-to-site and spatially and temporally within a site. A number of ex situ analytical processes are available to provide information that can help assess bioremediation but the sheer complexity and heterogeneity of the processes involved seriously limit their usefulness. In order for rapid advances and cost reductions to occur in the use of bioremediation, real-time monitoring of relevant parameters in situ in the subsurface are needed. Lynntech proposes to develop a microbial biosensor that provides highly relevant, real-time information needed to efficiently implement bioremediation strategies. The proposed sensor utilizes microorganisms directly involved in bioremediation that are native to the contaminated site of interest and acts as a real-time gauge of bioremediation activity. Combining a network of these sensors with traditional analytical methods permits the mapping of bioremediation with an unprecedented level of accuracy and relevance and will be critical to understanding and ultimately controlling the complex biogeochemical processes involved in bioremediation. Successful development of these sensors will provide a means to rapidly develop and optimize site-specific bioremediation strategies that are more effective and far less costly than current approaches. PUBLIC HEALTH RELEVANCE: Heavy metal contamination of subsurface environments such as soil, sediment, and groundwater is a worldwide threat to human health. Lynntech is proposing to develop a sensor to provide real-time monitoring of heavy metal bioremediation leading to more effective and less costly methods of removing heavy metal contamination from subsurface environments.